The present invention relates generally to removable screws, and more particularly to removable screws having an elongated protruding head. The disclosed removable screws may be particularly effective for use in assembling wood forms used to form concrete.
Current methods for assembling concrete forms often involve the use of common duplex nails and/or common wood screws. For example, a wood form board can be stabilized by attaching a stake (e.g., metal, wood) to the form board via common duplex nails. A wood form board can also be attached to an adjacent wood form board via common duplex nails. FIG. 1 illustrates an installed common duplex nail 2 joining a wood stake 4 to a form board 6. After the concrete has been poured and sufficiently cured, the concrete forms are disassembled by removing the common duplex nails.
There are, however, some problems associated with the use of common duplex nails to assemble concrete forms. For example, while a duplex nail is easy to remove from stakes and form boards, it may be cumbersome to insert. In addition, when using duplex nails, a stake may come loose from a form board and/or a form board may come loose from another form board. When used with wood stakes, the duplex nails may cause the stakes to split.
With the advent cordless drills, common wood screws have been used to attach stakes to form boards and/or to attach form boards to other form boards. Screws may be easy to insert than duplex nails in some instances and allow for a stronger and tighter bond between the stake and form board (and between form boards).
The common wood screw, however, may be more difficult to remove than a duplex nail during disassembly of a concrete form. The head of the screw may get buried into a form member to an extent that it cannot be reached for removal. The head of the screw may become occluded with concrete such that a removal bit cannot be inserted into the screw head. The head of the screw may also become stripped. When used with a wood stake, the common wood screw may also cause the stake to split.
As such, there is a need for an improved removable fastener, particularly one that can be used to assemble concrete forms.